A Challenging, Rewarding Series of Models - Tips for Successful Completion I am truly impressed with this kit. Its designers are highly skilled wizards. Parts are smoothly cut by laser, and for wood parts, tolerances are tightly held. If you are a value seeker, this is an excellent value. If you are mechanically minded, chances are you will love these wooden puzzles/projects/models. If you don’t have model building or similar experience, this is an advanced project that could be a bit much for a first puzzle. I might suggest that you find a similar, simpler model to try first if you are apprehensive about completing a more complicated UGears project like this one. It may not turn out well if you deviate from the directions, or don’t carefully follow the assembly sequence and visuals. What you need will be there, but may not be obvious at first. I found the Hexapod to be a fairly complex project, suitable for those with patience and some mechanical experience or model building skills. For a beginner, a simpler kit could be a great learning tool. This particular kit isn’t a suitable birthday gift for your average teenager - certain skills are assumed which some may not have. The wood parts come in several sheets of fairly soft 1/8” or 3mm plywood (known as lite-ply to model airplane aficionados). They are very accurately cut with a computer-controlled laser cutter. Some extra parts that could be easily broken or lost during assembly are included. Each part is labeled with adjacent part numbers, although the parts themselves aren’t numbered. Some parts are marked with small reference marks or dots to aid in establishing the correct orientation during assembly. The manual lacks verbal instructions. The assembly diagrams are accurate, complete, but completely visual, with perhaps a few exceptions. One has to be very careful when examining the assembly pictures – a few differences are subtle, without clarification. Look quite carefully at the assembly diagrams, and use the numbers in the manual judiciously. Don’t jump ahead. If you do, you may not be happy with the problems that this might create. UGears supplies wax to lubricate the parts where they slide or rub together. It would be nice if more wax was furnished. Wood waxes can differ significantly. They say candle wax or paraffin can be used. The supplied wax seems to be softer than paraffin. It seems slightly slipperier than several other waxes I tried. It is softer and a bit “stickier” when rubbed on the wood. It seems a bit better than harder paraffin wax, or a few other commercially available wood lubricants I tried. A few square inches of 220 grit paper are supplied to smooth out parts in contact (which is too coarse in my opinion) to reduce wood-on-wood friction, and over-sanding with coarse paper may change tolerances. I used 400 grit then 1000 grit paper, which results in a smoother surface and less friction. Parts preparation is the key to end up with a smoothly operating model, so I spent a lot of time here. Do not over-sand, because it may change tolerances on bearings and other moving parts, which is to be avoided. Suggestions: Try a simpler kit to start with, as a learning experience for a more difficult kit. A simpler kit as a learning experience may help some to become a fan of these products, who would otherwise would become frustrated with more complex first-time project. Friction is the enemy of a properly working, powered wood model. Moving parts that have been waxed may need to be rubbed or worked in, or burnished. Where they say to use wax, you should wax adjacent moving or sliding surfaces, like the sides of gears. Thickly applied wax does not result in decreased friction. It may help if the wax is “worked in” by working the moving surfaces together, or burnishing, then perhaps reapplying wax. I did some homework regarding lubrication for wood-on-wood sliding surfaces. Experimenting some, I tried several commercially available wood lubricants without significant results. I found that graphite and/or molybdenum disulfide powder allied to waxed surfaces (or added to melted wax) did decrease wood-on-wood friction after waxing. But it created problems, too. Graphite is messy and dark, so if you are looking for a wood model for a display case, forget that. I wanted the Hexapod to operate smoothly and look like something prehistoric so I stained the parts dark, with water-diluted acrylic paint, which covered up the use of graphite. Others have had issues with broken parts. Use the included “tool” to punch the parts out of the plywood sheets. If a part is tight, work around the part gently and slowly rather than punching it out with one push. I put a thick towel on my work surface. This provides a soft pliable surface to punch out the parts from the plywood surround. Lots of light on your workspace is helpful. Be gentle and carefully align mating parts when assembling. Try to keep parts at right angles to one another when snapping parts together. If you have to force something, or a part doesn’t snap together like the rest, chances are you may have chosen the wrong parts to assemble. Broken parts can be repaired easily with just a dab of superglue. Don’t separate the parts from the plywood before you use them, to avoid difficulties later on. If some smaller parts come loose prematurely, scotch tape them back in place until called for, to maintain their identity. This kit has hundreds of parts, some of which look identical but aren’t, or can be identical with different part numbers (mirror image parts). Leave the tie-wrap or nylon tie on the metal spring before installing it. I lightly oiled my spring with sewing machine oil, then wiped off the excess from the edges. Assembling, dis-assembling, and reassembling parts loosens the fit between parts. The more it’s done, the looser the fit. Avoid using superglue to keep parts together and in place if you can – chances are you will have to backtrack somewhere during the assembly procedure. Follow the assembly guide exactly, step by step, page by page. Sanding and waxing is critical if your Hexapod is to operate as advertised. I over-sanded a few of the moving surfaces, specifically the round bearing surfaces. Consequently, it changed tolerances enough and added some “slop” that affected the motion of the Hexapod. One leg wouldn’t move far enough because of over-sanding and enlarged tolerances, so it fell over instead of crawling. Some parts looked and felt like they were tightly and properly snapped together, but on reinspection, they weren’t. If your Hexapod or other mechanical model doesn’t operate as expected, this could be the cause. It is easy to confuse look-alike parts. Review the manual carefully before starting the construction, to learn the syntax of the directions, which can be confusing and not particularly intuitive. The plywood can be successfully stained with lightly applied, water-diluted acrylic paint, and probably, with water color or spray paint as well (but I haven’t tried these). Leaving a paint build-up on the surfaces may change tolerances and increase friction. Perhaps spray on the paint lightly, then immediately wipe excess paint from just-painted surfaces?
